A known device is disclosed in International Publication No. WO99/11479. The known device in the publication is mounted on an opening portion of a vehicle roof and has a plurality of movable panels, and each movable panel is movable between a normal position covering a part of the opening portion of the roof and an operation position in which a rear end portion of the movable panel is raised with a front end portion of the panel as a pivoting point. Also, the known device has a groove portion mounted in a front end of each movable panel, and the groove portion is extended in a width direction of a vehicle and is opening in an upward direction relative to the vehicle. The known device is structured in that when the movable panel moves to the operation position, water (rainwater etc.) on the movable panel is converged at a groove portion formed in the front portion of the movable panel.
However, even when the movable panel moves to the operation position, in other words, when the rear end portion of the movable panel is raised, the water on the movable panel runs toward the rear end portion because of a direction of air flow on the vehicle when the vehicle is running. As a result, there is a possibility that the water comes inside of the vehicle through an opened space formed by raising the rear end of the movable panel.